What Do Other Religions Believe? A Comparative Look at Judaism, Christianity, and Islam

Judaism's engagement with other religions is shaped primarily by its foundational commitment to ethical monotheism and the covenant between God and the Jewish people. The Hebrew Bible doesn't spend much time cataloguing what other religions believe in a neutral, descriptive sense—it's far more concerned with warning Israelites against being drawn toward those beliefs.

Deuteronomy is particularly direct. The text cautions that even a prophet who performs a genuine sign could be leading Israel astray if the message is "Let us follow and worship another god" Deuteronomy 13:3. The implication is that other religions, however compelling their external claims, are evaluated against the standard of loyalty to the God of Israel. Similarly, Deuteronomy 30:17 frames turning to other gods as a matter of the heart turning away—a spiritual defection rather than merely an intellectual error Deuteronomy 30:17.

Jeremiah reinforces this by connecting national catastrophe directly to religious infidelity: the people "forsook the covenant with the ETERNAL their God and bowed down to other gods and served them" Jeremiah 22:9. Other religions, in this framing, aren't simply different paths—they represent a rupture of relationship.

That said, rabbinic Judaism developed a more nuanced framework over time. The Noahide Laws, discussed extensively in the Talmud (Sanhedrin 56a–60a), hold that non-Jews are bound by seven universal moral commandments and can be considered righteous without converting. Scholar David Novak, in his 1983 work The Image of the Non-Jew in Judaism, traced how this framework allowed Judaism to acknowledge moral and even spiritual validity in other traditions without abandoning its own exclusivist claims. There's genuine disagreement among Orthodox, Conservative, and Reform thinkers about how far that acknowledgment extends.

Christianity inherits the Hebrew Bible's wariness of polytheism and idol worship, but adds a distinctly Christological dimension: the question isn't only whether one worships the right God, but whether one recognizes Jesus as the Christ. This creates a more complex relationship with other religions than Judaism's covenant-centered framework.

The New Testament passages most often cited in this debate—John 14:6 ("I am the way, the truth, and the life") and Acts 4:12—push toward exclusivism. Yet Christian theologians have disagreed sharply about what this means in practice. Karl Rahner's 20th-century concept of "anonymous Christians" argued that sincere adherents of other faiths could be saved through Christ without explicit knowledge of him—a position the Second Vatican Council (1962–1965) partially endorsed in Nostra Aetate, which acknowledged truth and holiness in non-Christian religions.

On the other end, scholars like Lesslie Newbigin (in his 1989 work The Gospel in a Pluralist Society) argued that Christian mission requires maintaining the particularity of Christ's revelation rather than dissolving it into a generic pluralism. Protestant evangelical traditions tend toward a stricter exclusivism, while mainline Protestant and Catholic traditions have moved toward varying degrees of inclusivism or even pluralism.

What other religions believe, from a Christian standpoint, is thus evaluated through this lens: do their beliefs align with, partially reflect, or contradict the revelation in Christ? The answer varies enormously depending on which Christian tradition you ask.

Islam takes a distinctive position: it doesn't merely evaluate other religions from the outside but claims to correct and complete them. The Qur'an presents Islam not as a new religion but as the restoration of the original, universal submission to God (Arabic: islam, meaning submission) that all prophets taught.

Quran 3:83 frames this cosmically: "Seek they other than the religion of Allah, when unto Him submitteth whosoever is in the heavens and the earth, willingly or unwillingly, and unto Him they will be returned" Quran 3:83. In this view, other religions that worship anything besides Allah are not simply different—they're pursuing something that contradicts the fundamental nature of creation itself.

Quran 37:86 sharpens the critique of polytheism directly: "Is it falsehood [as] gods other than Allāh you desire?" Quran 37:86. This rhetorical question frames the worship of other deities as a kind of self-deception.

The Qur'an also distinguishes between sincere and insincere belief. Quran 2:8 notes that some people claim belief without genuine conviction Quran 2:8, which implies Islam is concerned not just with formal religious affiliation but with the authenticity of faith.

Classical Islamic jurisprudence developed the concept of Ahl al-Kitab (People of the Book)—Jews and Christians primarily—who receive a degree of theological respect as recipients of earlier revelation, even if that revelation is considered corrupted. Scholar Seyyed Hossein Nasr, in his 2004 work The Heart of Islam, argued that traditional Islamic thought contains genuine resources for religious pluralism, though this remains contested among contemporary Muslim scholars and movements.

Judaism teaches that turning one’s heart away to “worship and service of other gods” is forbidden and leads Israel away from life with God. Deuteronomy 30:17

Prophetic literature explains calamity as the result of forsaking the covenant and bowing to other gods. Jeremiah 22:9

Even if a sign or portent comes true, Israel must not follow anyone urging worship of another god. Deuteronomy 13:3

Christianity, receiving the Hebrew scriptures, upholds their command that God’s people must not turn to or worship “other gods.” Deuteronomy 30:17

It warns—echoing the prophets—that forsaking God’s covenant to serve other gods brings judgment. Jeremiah 22:9

Christians are thus to reject any teacher or sign that would entice them to follow another god. Deuteronomy 13:3

Islam proclaims that all in the heavens and the earth ultimately submit to Allah and will return to Him, underscoring exclusive devotion. Quran 3:83

It rejects the desire for gods other than Allah as falsehood. Quran 37:86

It also cautions that merely claiming belief in Allah and the Last Day does not constitute true faith. Quran 2:8